Buggy code:
, new MethodGenerator ( ) { @ Override public void generateMethod ( ) { utils . println ( "this.nativeObject<seq2seq4repair_space>=<seq2seq4repair_space>nativeObject;" ) ; } } ) ; utils . generateMethod ( "public" , "JavaScriptObject" , "getNativeObject" , null , new MethodGenerator ( ) { @ Override public void generateMethod ( ) { utils . println ( "return<seq2seq4repair_space>nativeObject;" ) ; } } ) ; utils . generateMethod ( "public" , "String" , "getId" , null , new MethodGenerator ( ) { @ Override public void generateMethod ( ) { utils . println ( "return<seq2seq4repair_space>getId(nativeObject);" ) ; } } ) ; utils . generateNativeMethod ( "private" , "String" , "getId" , new String [ ] [ ] { new String [ ] { "JavaScriptObject" , "nativeObject" } } , new MethodGenerator ( ) { @ Override public void generateMethod ( ) { utils . println ( "return<seq2seq4repair_space>nativeObject.id;" ) ; } } ) ; utils . generateMethod ( "public" , "<T<seq2seq4repair_space>extends<seq2seq4repair_space>Persistable><seq2seq4repair_space>void" , "fetch" , new String [ ] [ ] { new String [ ] { "Transaction" , "transaction" } , new String [ ] { "Entity<T>" , "entity" } , new String [ ] { "ScalarCallback<T>" , "callback" } } , new MethodGenerator ( ) { @ Override public void generateMethod ( ) { utils . println ( "EntityInternal<T><seq2seq4repair_space>entityInternal<seq2seq4repair_space>=<seq2seq4repair_space>(EntityInternal<T>)entity;" ) ; utils . println ( "fetch(transaction,<seq2seq4repair_space>entityInternal.getEntityName(),<seq2seq4repair_space>entityInternal,<seq2seq4repair_space>callback,<seq2seq4repair_space>this,<seq2seq4repair_space>nativeObject);" ) ; } } ) ; utils . generateMethod ( "public" , "<T<seq2seq4repair_space>extends<seq2seq4repair_space>Persistable><seq2seq4repair_space>void" , "fetch" , new String [ ] [ ] { new String [ ] { "Entity<T>" , "entity" } , new String [ ] { "ScalarCallback<T>" , "callback" } } , new MethodGenerator ( ) { @ Override public void generateMethod ( ) { utils . println ( "fetch(null,<seq2seq4repair_space>entity,<seq2seq4repair_space>callback);" ) ; } } ) ; utils . generateNativeMethod ( "private" , "<seq2seq4repair_space><T<seq2seq4repair_space>extends<seq2seq4repair_space>Persistable><seq2seq4repair_space>void" , "fetch" , new String [ ] [ ] { new String [ ] { "Transaction" , "transaction" } , new String [ ] { "String" , "property" } , new String [ ] { "EntityInternal<T>" , "entity" } , new String [ ] { "ScalarCallback<T>" , "callback" } , new String [ ] { ( requestedClassName ) + "Impl" , "self" } , new String [ ] { "JavaScriptObject" , "nativeObject" } } , new MethodGenerator ( ) { @ Override public void generateMethod ( ) { utils . println ( "nativeObject.fetch($wnd.persistence,<seq2seq4repair_space>transaction,<seq2seq4repair_space>property,<seq2seq4repair_space>function(result)<seq2seq4repair_space>{" ) ; utils . sw ( ) . indent ( ) ; utils . println ( "self.@%s.%s.%sImpl::processFetchCallback(Lcom//google//gwt//core//client//JavaScriptObject;Lcom//gwtmobile//persistence//client//EntityInternal;Lcom//gwtmobile//persistence//client//ScalarCallback;)(result,<seq2seq4repair_space>entity,<seq2seq4repair_space>callback);" , utils . getPackageName ( requestedClassName ) , generatedClassName , requestedClassName ) ; utils . sw ( ) . outdent ( ) ; utils . println ( "});" ) ; } } ) ; utils . generateMethod ( "private" , "<T<seq2seq4repair_space>extends<seq2seq4repair_space>Persistable><seq2seq4repair_space>void" , "processFetchCallback" , new String [ ] [ ] { new String [ ] { "JavaScriptObject" , "result" } , new String [ ] { "EntityInternal<T>" , "entity" } , new String [ ] { "ScalarCallback<T>" , "callback" } } , new MethodGenerator ( ) { @ Override public void generateMethod ( ) { <START_BUG> utils . println ( "callback.onSuccess(entity.newInstance(result));" ) ; <END_BUG>

Fix:
utils . println ( "callback.onSuccess(result<seq2seq4repair_space>==<seq2seq4repair_space>null<seq2seq4repair_space>?<seq2seq4repair_space>null<seq2seq4repair_space>:<seq2seq4repair_space>entity.newInstance(result));" ) ;